1. Field of the Invention
This invention generally relates to power wrenching machines and more particularly to such machines that utilize a ratcheting-type wrench for turning threaded fasteners, such as nuts and bolts.
2. Description of the Prior Art
A power wrenching machine of the foregoing type is described in U.S. Pat. No. 4,091,890, assigned to the same assignee. The patented machine is now widely used on flanged and other connections having threaded fasteners. Other such machines are also known from U.S. Pat. Nos. 3,745,858 and 3,930,776.
The patented machines have in common a hydraulically-operated ram and a ratcheting-type wrench. The ram is directly and pivotably connected to the wrench for transmitting a perpendicular force to the wrench, as more fully explained in Column 3, Lines 37-63 of said U.S. Pat. No. 4,091,890.
In said patents U.S. Pat. Nos. 3,745,858 and 3,930,776 the ratchet wrench and the hydraulic ram are mounted on a common frame. Because of the long felt need to pivotably connect the ram to the wrench at an angle which is substantially 90.degree., it was also felt that the height of the machine could not be made less than the length of the employed wrench.
Hence, the height-to-length (H/L) ratio of such known machines is relatively substantial, and for that reason the machines cannot be used in installations providing limited access to their threaded fasteners which it is desired to rotate. In limited installations in which access to the threaded fasteners is available only through a very narrow channel, the tightening or loosening operations are now being carried out with improved tooling and by utilizing a considerable amount of hand labor.
Thus, the need for machines of the foregoing class having a relatively small H/L ratio has remained unfulfilled, and the drawbacks of known machines have been unsatisfactorily resolved.
It is an object of the present invention to provide such a rugged and dependable wrenching machine having a small H/L ratio. The height of the machine is substantially independent of the length of the wrench used within the machine. Its small height makes it possible for the novel machine to operate in installations wherein access to a threaded connector is available only through a narrow channel which is substantially parallel to or coincident with the head of the fastener to be rotated.
An additional object is to provide a new and improved power wrenching machine having a minimum of moving parts that are arranged in tandem along the length dimension of the machine, and are adapted to transfer high forces therebetween.